#!/bin/sh

##This file is mostly fixes stolen directly from the recommendations of powertop.
# For the sake of completeness we will include the fixes we don't want and comment them out with reasoning
# XXX: This should be rewritten into acpid and this file should just be an initial call to acpid default.sh
#---------------------------------------------------------------------------------------------------------

##PM runtime (PCI Devices)
##this links to usb and disables usb devices that suck
#for i in `find /sys/devices/pci* -name "control"`; do echo "auto" > $i; done

##USB Suspend
#currently this kills usb mice, and stops my cell phone from charging
#for i in $(\ls -1 /sys/bus/usb/devices)
#do
#	usb_path="/sys/bus/usb/devices/${i}"
#	if [ -L ${usb_path}/driver ]
#	then
#		if [ "$(ls -al ${usb_path}/driver | grep usbhid)" == "" ]
#		then
#			echo "Enabling power saving for non-input device ${usb_path}"
#			ls -al ${usb_path}/driver
#			[ -e ${usb_path}/power/autosuspend ] && echo 1 > ${usb_path}/power/autosuspend
#			[ -e ${usb_path}/power/level ] && echo auto > ${usb_path}/power/level
#			[ -e ${usb_path}/power/control ] && echo auto > ${usb_path}/power/control
#		else
#			echo "Not enabling power saving for input device ${usb_path}"
#			ls -al ${usb_path}/driver
#		fi
#	fi
#done

# allowing to not sync the drive for longer on battery means more lost when we run out of battery, not a fan
#echo 1500 > /proc/sys/vm/dirty_writeback_centisecs

## This TANKS wifi performance way too much
#iwconfig wlan0 power timeout 500ms

#intel sound
if [ -e /sys/module/snd_hda_intel/parameters/power_save ]; then
	echo 1 > /sys/module/snd_hda_intel/parameters/power_save
fi


##Making devices take longer to power save means more draw
#USB suspend tweaking based on Linux/Documentation/usb/power-management.txt
#Change the default autosuspend idle value from 2sec to 60sec
#for i in /sys/bus/usb/devices/*/power/autosuspend_delay_ms; do echo 60000 > $i; done
#echo 60 > /sys/module/usbcore/parameters/autosuspend

#disable NMI watchdog (unless we are running a redundant kernel we don't need this)
if [ -e /proc/sys/kernel/nmi_watchdog ]
then
	echo 0 > /proc/sys/kernel/nmi_watchdog
fi

if [ -e /sys/devices/system/cpu/sched_mc_power_savings ]
then
	echo 1 > /sys/devices/system/cpu/sched_mc_power_savings
fi

##then the battery specific power savings
scsi_path="/sys/class/scsi_host/"
cpu_path="/sys/devices/system/cpu/"

if [ "$(cat /sys/class/power_supply/AC*/online)" == "0" ]; then
	#battery
	for CPU in $(\ls  ${cpu_path}|grep -E "cpu[0-9]+"); do
		[ -e ${cpu_path}/${CPU}/cpufreq/scaling_governor ] && echo conservative > ${cpu_path}/${CPU}/cpufreq/scaling_governor
	done
	for controller in $(\ls ${scsi_path}|grep -E "host[0-9]+"); do
		[ -e ${scsi_path}${controller}/link_power_management_policy ] && echo min_power > ${scsi_path}${controller}/link_power_management_policy
	done
else
	#AC
	for CPU in $(\ls  ${scsi_path}|grep -E "cpu[0-9]+"); do
		[ -e ${scsi_path}${CPU}/cpufreq/scaling_governor ] && echo ondemand > ${scsi_path}${CPU}/cpufreq/scaling_governor
	done
	for controller in $(\ls ${scsi_path}|grep -E "host[0-9]+"); do
		[ -e ${scsi_path}${controller}/link_power_management_policy ] && echo max_performance > ${scsi_path}${controller}/link_power_management_policy
	done
fi
